XStream:将XML的一部分保留为XML

时间:2011-08-31 10:47:54

标签: java xml xstream

我有以下XML:

<patient>
    <name>Mr. Sick</name>
    <report>
        <paragraph><bold>Conclusion</bold>text...</paragraph>
    </report>
</patient>

我想将此转换为类似患者的实例,如下所示:

Class Patient {
    String name = "Mr. Sick";
    String report = "<paragraph><bold>Conclusion</bold>text...</paragraph>";
}

是否可以使用XStream仅转换部分XML并将报告字段保持为XML格式?怎么办呢?

3 个答案:

答案 0 :(得分:4)

我通过创建转换器实现来解决它,如here所述。我对此问题的解决方案如下:

Patient.java

public class Patient {
    String name;
    Report report;
}

Report.java

public class Report {
    public String report;
}

转换器for XStream的实现

public class ReportConverter implements Converter { 

    @Override 
    public boolean canConvert(Class classs) { 
        System.out.println("canConvert: " + classs.getName());
        return classs.equals(Report.class); 
    } 

    @Override 
    public void marshal(Object value, HierarchicalStreamWriter writer, 
            MarshallingContext context) {
        // not used in this example
    } 

    // goes recursive through all the nodes in <report>
    String getNodeAsText(HierarchicalStreamReader reader) {
        String result;
        result = "<" + reader.getNodeName() + ">" + reader.getValue();
        while (reader.hasMoreChildren() ) {
            reader.moveDown();
            result += getNodeAsText(reader);
            reader.moveUp();
            result += reader.getValue();
        }
        result += "</" + reader.getNodeName() + ">";
        return result;
    }

    @Override 
    public Object unmarshal(HierarchicalStreamReader reader, 
            UnmarshallingContext context) {
        Report xReport = new Report();
        xReport.report = reader.getValue();
        while (reader.hasMoreChildren() ) {
            reader.moveDown();
            xReport.report += getNodeAsText(reader);
            reader.moveUp();
            xReport.report += reader.getValue();
        }
        return xReport; 
    } 
}

使用XStream转换器的示例

XStream xStream = new XStream();
xStream.registerConverter(new ReportConverter());
xStream.alias("patient", Patient.class);
xStream.alias("report", Report.class);
String xml = "<patient><name>Mr. Sick</name><report><paragraph>" +
        "some text here<bold>Conclusion</bold>text...</paragraph>" +
        "<sdf>hello world</sdf></report></patient>";
Patient patient = (Patient)xStream.fromXML(xml);
System.out.println("patient.name: " + patient.name);
System.out.println("patient.report: " + patient.report.report);

输出

patient: Mr. Sick
patient.report: <paragraph>some text here<bold>Conclusion</bold>text...
    ...</paragraph><sdf>hello world</sdf>

答案 1 :(得分:3)

我没有得到问题的答案,但我建议一个可能有帮助的替代方案。

您可能应该转义report字段的内容。这将帮助您避免无效的xml,这在解组时可能会非常有问题。

这是一种简单的方法(使用来自apache org.apache.commons.lang.StringEscapeUtils的公共libray):

class Patient {
   String name = "Mr. Sick";
   String report = StringEscapeUtils.escapeHtml(
         "<paragraph><bold>Conclusion</bold>text...</paragraph>");

  // report = "&lt;paragraph&gt;&lt;bold&gt;Conclusion&lt;/bold&gt;text...&lt;/paragraph&gt;"
}

答案 2 :(得分:2)

更好的getNodeAsText()版本,包含每个节点的属性:

private String getNodeAsText(HierarchicalStreamReader reader) {

StringBuilder str = new StringBuilder();
str.append("<")
   .append(reader.getNodeName());

for (int i = 0; i < reader.getAttributeCount(); i++) {
  String name = reader.getAttributeName(i);
  String value = reader.getAttribute(i);
  str.append(" ")
     .append(name)
     .append("=\"")
     .append(value)
     .append("\"");
}
str.append(">")
   .append(reader.getValue());

while (reader.hasMoreChildren()) {
  reader.moveDown();
  str.append(getNodeAsText(reader));
  reader.moveUp();
  str.append(reader.getValue());
}
str.append("</")
   .append(reader.getNodeName())
   .append(">");

return str.toString();

}

StringBuilder str = new StringBuilder(); str.append("<") .append(reader.getNodeName()); for (int i = 0; i < reader.getAttributeCount(); i++) { String name = reader.getAttributeName(i); String value = reader.getAttribute(i); str.append(" ") .append(name) .append("=\"") .append(value) .append("\""); } str.append(">") .append(reader.getValue()); while (reader.hasMoreChildren()) { reader.moveDown(); str.append(getNodeAsText(reader)); reader.moveUp(); str.append(reader.getValue()); } str.append("</") .append(reader.getNodeName()) .append(">"); return str.toString();